Circuit breaker



June 24, 1947: Q JENSEN 2,422,784

' bIRcUIT BREAKER 7 Filed Sept. 50, 1944 2 Sheets-Sheet 1 28 IN VEN TOR.

OTTO JENSEN Z- ATTORNEY June 24, 1947. o. JENSEN 2,422,784

CIRCUIT BREAKER Filed Sept. 50, 1944 2 Sheets- Sheet 2 IN VEN TOR.

OTTO d ENSEN ATTORNEY Patented June 24, 1947 UNITED STATES PATENT OFFICECIRCUIT BREAKER Application September 30, 1944, Serial No. 556,502

8 Claims. 1

My present invention relates to circuit breakers and more particularlyto high speed air blast circuit breakers intended to carry relativelyheavy currents at high voltage.

My invention contemplates the formation of an air blast circuit breakerin the form of a simple vertical structure embracing the contactmechanisms and the arc chute mounted by means of an insulator on an airstorage tank.

My invention also contemplates the arrangement of contacts of thecircuit breaker so that they will be aligned in the principal directionof air blast flow, preferably vertically aligned; but the circuitbreaker structure will be so arranged that the air blast at the momentit strikes the arc caused by the separation of the contacts will besubstantially transverse to the said arc.

My invention thus contemplates retaining all of the advantages ofvertical movement of the air blast substantially along the path ofseparation of the contacts combining therewith, however, a somewhatsinusoidal internal arrangement which will enable the blast to strikethe arc transversely at the area in which the arc is generated.

Accordingly, a primary object of my invention is the formation of an airblast circuit breaker having a novel arc chute. A corollary object of myinvention is the formation of an air blast arc chute so arranged thatalthough the air will move substantially along the path of movement ofthe contacts, the air blast will strike the arc transversely at its areaof generation.

Another object of my invention is a novel formation of arc extinguishinghorns and a novel arrangement for providing a by-pass current for thearc extinguishing system.

Another object of my invention is the arrangement of the circuit breakerso that the initial opening movement of the movable contact breaks thecurrent flow while further movement isolates the arc horn connected tothe movable contact terminal through the movable contact and thusprovides an isolation switch.

Another object is the formation of the air blast path so that in theevent an arc should maintain itself even in the isolation position ofthe contact, it will be subject to a. transverse blast.

These and many other objects of my invention will become apparent in thefollowing specification and drawings in which Figure 1 is a side view incross-section of my novel circuit breaker;

Figure 2 is a cross-sectional view taken on line 2-2 of Figure 1 lookingin the direction of the arrows.

Referring now to Figures 1 and 2, the contact arrrangement consisting ofthe main stationary contact structure In, the main movable contactstructure II, and the intermediate contact 2 structure i2, have alreadybeen specifically described in the co-pending application of ArthurCaswell, Serial No. 529,439, filed April 4, 1944, entitled Circuitbreaker contacts, and assigned to the assignee of the presentapplication.

The are extinguisher 13 has been more specifically described in theco-pending application of Otto Jensen, Serial No. 406,813, filed August14, 1941 (now Patent No. 2,353,729, and assigned to the assignee of thepresent invention.

The circuit breaker itself comprises a principal housing 20 which issecured by bolts 2| and a clamping ring 22 to the lower connectingmember 23, which has a terminal 24. The entire circuit breaker structurein the housing 20 is mounted on the lower hollow insulator 25 which hasthe internal air passage 26.

Insulator 25 is preferably mounted on top of a compressed air tank andsuitable controls may be provided therefor, as for instance described inthe co-pending application of Otto Jensen et 211., Serial No. 410,260,filed September 10, 1941. The upper end of the insulator 25 has areinforcing collar 28 secured thereto in any suitable manner and agasket or washer 29 is placed between the collar 28 and the connectingmember 23, and the connecting member 23 is bolted to the collar 28 bythe bolts 30 which may be provided with suitable insulating bushings.

The main movable contact ll comprises a vertical sliding rod having anarcing contact surface 32 and. main contact surfaces 33, 33. The mainstationary contact I0 is provided with main stationary contact members34, 34 and an arcing contact member 35. The main stationary contactmembers 34 and the arcing contact 35 are secured in a housing 31 at theend of the curved conductive bar 38. The curved conductive bar 38 isprovided with lateral flanges 39 and 40, which are secured by means ofbolts 4|, 4| to the side internal frame supporting collars 42, 42.

These frame supporting collars 42 are secured to the sides of thehousing 20 by means of bolts 43, 43. The conductive bar 38 is curved at38a to form an arc horn. The upper terminal 45 of the circuit breaker issecured by means of the bolt 46 to the end of the conductive bar 38. Theupper end of the arc horn 38a. has an upwardly extending connectingtongue 41 which is condglctively engaged by the clip 48 of the arc chutel The intermediate contact members l2 comprise a pair of oppositecontacting elements 50, 50 which may contact with the sides of themovable contact member while it is between them. The members forming theintermediate contact l2 are contained in the housing 52 which is securedby bolts 53, 53 to the centrally located internal collar 55 within thehousing.

The internal supporting collar 55 is supported from the upper collar 42by means of the post 60 which is secured by the bolt 6| to the uppersupporting collar 42 and by the bolt 62 to the lower supporting collar55. It is also supported from the upper supporting collar by theinsulating tube 65 which is, at 56, threaded into an appropriate opening51 of the lower supporting collar 55, and which tube is at the upper endclosed by the plug 69 and secured to the upper supporting collar 55 bythe bolt 88.

The intermediate or lower supporting collar 55 is a substantially solidmember except for the opening I through which the movable contact memberpasses, and the opening 51 which provides a passage for the blast air.The upper supporting collar 42 is substantially solid and closed at thecenter and at its left-hand side, but is substantially open and consistssubstantially of a pair of spaced tines at its right-hand side toprovide a free passage for air. Also the collar 42 does not extendentirely over to the righthand wall (Figure 1) of the housing 20, sothat a free passage for the arc horn I38a is provided.

As will be seen, current enters through the upper terminal 45, passesalong the arcing horn 38a to the upper contact structure I0; then passesthrough the movable contact II when the same is in engagement with theupper contact structure; then through the lower connecting member 23 tothe lower terminal 24.

As described in co-pending application of Arthur S. Caswell, abovementioned, the main stationary contact members 31 are pressed toward themovable contact by means of the springs 15.

They are also pressed downwardly by the spring in order to engage thebottom wall 11 cf the housing which is in close conductive relation withthe connecting bar 38.

The arcing contact member is spring compressed by means of the spring 80toward the movable contact. When the movable contact has engaged thestationary contact, the arcing contact surface 32 forces the stationaryarcing contact 35 back, so that the main contact surfaces 33 of themovable contact may engage the main contact surfaces 34 of thestationary contact.

The intermediate contact elements are pressed toward the movable contactby means of the spring 82 in the same manner as are the stationarycontact members, and are pressed into conductive engagement with theirhousing by means of the springs 83. Thus, the movable contact may slidewith respect to the intermediate contact elements 50 of the intermediatecontact I2, and carry current thereto.

The lower connecting member 23 also carries a contact housing 90 securedthereto in any suitable manner, as for instance by the bolts 9|. Thecontact members 92, 92 in the lower contact housing 90 are biased intoengagement with the movable contact II by the springs 93 and are biasedinto engagement with their housing by the spring 94. The lower contactmembers 92 thus carry current from the movable contact II to the lowerconnecting member 23 and thence to the lower terminal 24.

In each case these various contact members avoid the necessity forflexible leads or pigtails. The intermediate contact section I2comprising the contact members 50, furnish the current for the arcinghorn I38a. That is, the arcing horn I38a is connected at its lower endto the upper portion of the housing for the intermediate contactstructure I2.

The air passage thus formed consists of the following: the tube 26 inthe insulating member 25, which tube extends substantially alongside thepath of movement of the lower movable contact II; the lower air chamberI00 is connected by the tube 65 to the area where the are is drawn; thetube 55 is provided with an opening I02 opposite the arcing area. Theair thus flows up the passage 26 into the chamber I00 and then throughthe relatively narrow tube 55, where the relatively confined exitopening provides for a high speed air blast. The air flows through theopening I02 into the section I04 where the arc is drawn, and then flowsup through the passage I05 into the upper chamber I05, and then into thearc extinguisher I3.

When the movable contact separates from the stationary contact, thecontact surfaces 33 and 34 separate first, while the spring drives thestationary arcing contact 35 toward the movable arcing contact 32 tomaintain engagement therebetween. The stationary arcing contact 35 isbrought to a stop by the flanges I09 only after the main contactsurfaces have separated. Consequently, the arc is drawn between thestationary arcing contact surfaces 35 and the movable arcing contactsurface 32.

The air blast is initiated at the time that the contacts begin toseparate so that by the time the arc is drawn between the arcing contactsurfaces in the area I04, the full force of the air blast strikes thearc. The arc is blown on to the arcing horns 38a and I38a and up intothe upper chamber I06, and then up into the arc chute I3 where it isextinguished.

A current supply is maintained to the lefthand arcing horn 30a by reasonof its connection to the terminal 45. A current supply for theright-hand arcing horn I38a of Figure 1 is provided from the movablecontact II through the intermediate contact structure I2, to which theright-hand arcing horn I38a is connected. The upper end of the arcinghorn I38a is provided with a tongue extension I I5, similar to thetongue extension 41 previously described, which tongue extension isengaged by the connecting clip H5 corresponding to the connecting clip48, previously described.

Arc horn I-38a is isolated from its terminal 24 when the moving contactII leaves the intermediate contact l2. Any arc which may neverthelesshang on between the arcing contact surfaces 32 and 35 after the movablecontact leaves the intermediate contact will be extinguished by thecross-blast in chamber I00.

The are extinguisher I3 has already been described in the application ofJensen, Serial No. 406,813, now Patent No. 2,353,729, and requires nofurther description here. Essentially, however, the arc is blown up intothe arc chute with the roots of the are at the terminal plates I20 andI2I, and into the arc extinguishing high resistance metallic plates I22.Each pair of plates I22 is connected together to form a high resistanceU-shaped plate, so that as the are is blown up between the adjacentU-shaped plate, the increasing resistance of the plates is inserted inseries with the arc in addition to the cooling effect of the plates.

The vented cover I30 for the entire structure also is described in thesaid application Serial No. 406,813, now Patent No. 2,353,729, and issecured to the top of the housing 20 by means of bolts I3:I passingthrough matching flanges I32, I33. The removal of the bolts I3I enablesremoval of the cover I30 and the withdrawal of the arc chute l3 which isconnected to the upper ends of the arcing horns only by the clips 48 andH6. After inspection of the are chute, it may be re-inserted through thetop of the housing so that the clips H6 and 48 engage respectively thetongues H5 and 41;

By the means herein described, a sinuous air blast arc chute is arrangedin such a manner that the air essentially travels longitudinally alongthe path of movement of the arc; but at the portion of the air pathWhere the air is directed against the arc, the path of movement of theair is transverse to the are. This arrangement therefore makes possiblethe simplified mounting of the entire circuit breaker structure right ontop of the air storage tank for the simplified short connection to theair storage tank which avoids the possibility of loss of pressure andreduces the occurrence of leaks.

Also this arrangement makes possible the com-- bination of a horizontalblast of air which is transverse to the movement of vertically movablecontacts with an overall vertical movement of the air. That is, the airblast up to the time it reaches the arc moves vertically and aft-er itengages the arc and blows the same into the arc chute, it again movesvertically.

The vertical upward movement of the air after the arc has been engagedavoids a substantial amount of back pressure and in fact utilizes thetendency of the heated or ionized air to rise to relieve the pressure.

In the foregoing I have described my invention only in connection with asimplified, readily understood embodiment thereof. tions andmodifications of my invention should now be clear to those skilled inthe art. Ac cordingly, I prefer to be bound not by the specificdisclosure herein but only by the appended claims.

I claim:

1. In a circuit interrupter having a movable contact and a complementarycontact, a fluid blast arc extinguisher comprising a principal chamber;and a source of fluid under pressure connected to said principalchamber; said principal chamber being arranged to direct said fluid in apath substantially parallel to the path of movement of the movablecontact; means controlled by said movable contact in the first part ofits movement for interrupting the circuit controlled by said interrupterand in the further movement effecting an isolating break in series withsaid interruption; and means in said chamber for directing said fluid ina sinuous path; said path intercepting the path of movement of themovable contact in a plurality of regions.

2. In a circuit interrupter having a movable contact and a complementarycontact, a fluid blast arc extinguisher comprising a principal chamber;and a source of fluid under pressure connected to said principalchamber; said principal chamber bein arranged to direct said fluid in apath substantially parallel to the path of movement of the movablecontact; and a partition in said principal chamber extending across thepath of movement of said movable contact; an opening in said partition;the end of said movable contact extending through said opening in saidpartition on one side of the partition when the contacts are engaged,said movable contact being withdrawn from said opening and on the otherside of said partition when said contacts are fully disengaged; theconnection be tween said source of fluid and said principal Many varia--chamber being atone side of the axis of said principal chamber; anadditional opening in said partition on the other side of the axis ofsaid principal chamber, the fluid being guided by said partition andsaid additional opening in a path transverse to the arc to extinguishany are which may extend from said complementary contact through saidfirst mentioned opening in the partition to the movable contact; meansabove said partition associated with said additional opening for guidingsaid fluid transversely of the path of movement of the movable contactin the region of initial separation of the contacts, said complementarycontact having an arcing horn associated therewith; said partitioncarrying an intermediate contact at its first mentioned opening; saidmovable contact engaging said intermediate contact only while saidmovable contact extends through said opening in said partition; anotherarcing horn connected to said intermediate contact.

3. In a circuit interrupter; a housing defining a principal chamber; amovable contact supported adjacent one end of said chamber; acomplementary contact supported in said chamber remote from said movablecontact; said movable.- contact being movable from the end of the cham--ber near which it is supported into engagement;

with said complementary contact; a partition in. said chamber betweensaid movable contact sup-- port and said complementary contact; anopening in said partition; said movable contact extending through saidopening when said contacts are engaged, and being remote from saidpartition when said contacts are fully disengaged, said complementarycontact having an arcing horn-associated therewith; said partitioncarrying an intermediate contact at said opening; said movable contactengaging said intermediate contact only while said movable contactextends: through said opening in said partition; another Larcting hornconnected to said intermediate con- 4. In a circuit interrupter; ahousing defining a principal chamber; a movable contact supportedadjacent one end of said chamber; a complementary contact supported insaid chamber remote from said movable contact; said movable contactbeing movable from the end of the chamber near which it is supportedinto engagement with said complementary contact; a partition in saidchamber between said movable contact support and said complementarycontact; an opening in said partition; said movable contact extendingthrough said opening when said contacts are engaged, and being remotefrom said partition when said contacts are fully disengaged, saidcomplementary contact having an arcing horn associated therewith; saidpartition carrying an intermediate contact at said opening; said movablecontact engaging said intermediate contact only while said movablecontact extends through said opening in said partition; another arcinghorn connected to said intermediate contact, said other arcing hornbeing electrically isolated when said contacts are fully disengaged;said partition providing a substantial barrier between said contactswhen said contacts are fully disengaged.

5. In a circuit interrupter; a housing defining a principal chamber; amovable contact supported adjacent one end of said chamber; acomplementary contact supported in said chamber remote from said movablecontact; said movable contact being movable from the end of the chambeernear which it is supported into engagement with said complementarycontact; a partition in said chamber between said movable contactsupport and said complementary contact; an opening in said partition;said movable contact extending through said opening when said contactsare engaged, and being remote from said partition when said contacts arefully disengaged, said complementary contact having an arcing hornassociated therewith; said partition carrying an intermediate contact atsaid opening; said movable contact engaging said intermediate contactonly while said movable contact extends through said opening in saidpartition; another arcing horn connected to said intermediate contact,and an arc chute connected to said are horns.

6. In a circuit interrupter having a movable contact and a complementarycontact, a fluid blast are extinguisher comprising an elongatedprincipal chamber; and a source of fluid under pressure connected tosaid principal chamber, a stationary contact being mounted at one end ofsaid chamber and said source of fluid under pressure at the other end ofsaid principal chamber,

said movable contact traversing said chamber axially, an intermediatecontact dividing said chamber into an interrupting section and anisolating section; and means in said chamber for guidin said fluid underpressure to traverse first said isolating section and then saidinterrupting section.

'7. In a circuit interrupter having a movable contact and acomplementary contact, a fluid blast arc extinguisher comprising anelongated insulated principal chamber; and a source of fluid= underpressure connected to said principal chamber; a stationary contact beingmounted atone end of said principal chamber and said sourceof fluidunder pressure being connected to the othe-rend-oisaid chamber, anarcing'horn, an intermediate contact connected to said arcing horn, saidmovable contact engaging both said intermediate and complementarycontacts in closed position and on opening disengagin said stationarycontact first and thereafter said interrn'ediate contact to form aninterruptin gap and an isolating gap; and means in said chamber forguiding said fluid traversing first the isolating gap and then saidintermediate gap during movement of the movable contact in the regionbetween the movable and complementary contacts.

8. In a circuit interrupter having a movable contact and a complementarycontact, a fluid blast arc extinguisher comprising an elongatedinsulating principal chamber; and a source of fluid under pressureconnected at one end of said principal chamber and a vent forcontaminated gas at the other end of said principal chamber, meansincluding said movable contact for establishin an interrupting break tobe followed by an isolating break in series within said chamber inresponse to the continuous movement of said movable contact; means insaid chamber for directing said fluid in a sinuous path to traverse theisolating break and then the interrupting break in the path of movementof said movable contact.

O'I'IO JENSEN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,067,048 Reher Jan. 12, 19372,287,03 Jansson June 23, 1942 FOREIGN PATENTS Number Country Date516,238 Great Britain Dec. 28, 1939

